Abstract

Wildlife tourism is a burgeoning global industry with the potential to make a significant contribution to
the conservation of endangered species. However, a number of studies have provided evidence that tourists’
presence and behaviour may impact negatively on the animals involved, with potentially harmful
consequences for their health, reproduction and population viability. Here, we investigate impacts of
tourism on wild male Barbary macaques (Macaca sylvanus) in Morocco, quantifying a behavioural index
of animals’ anxiety (self-scratching) and a measure of their physiological stress levels (faecal glucocorticoid
concentrations – FGCs). Four measures of tourist presence, number or proximity were explored:
maximum number, percentage of time present, mean number while present, and closest proximity to
the macaques. In addition, rates of three types of interactions between tourists and macaques – neutral
(e.g. photographing), feeding and aggressive – were quantified. Males’ rates of self-scratching were positively
related to the mean number of tourists present and to rates of all three human-macaque interactions,
but were unrelated to the other three measures of tourist pressure. FGCs were positively related to
rates of aggressive interactions between humans and macaques, but unrelated to any of the other six
measures of tourist pressure. These findings suggest that while tourist presence and interactions (even
apparently innocuous ones) with the macaques elevate the study animals’ anxiety levels, only aggressive
interactions are sufficient to elicit a detectable increase in our measure of physiological stress. These
results can be used to inform management of tourism both at this site, and at other locations where tourists
view and can interact with wild primates.